"De gustibus non est disputandum" is a popular saying, conveying that one shouldn't argue about flavors. Now, a team at the Weizmann Institute of Science, headed by Prof. Doron Lancet of the Molecular Genetics Department, has found why this is true.

In our genome, around 1,000 genes code for the nose's odor-detecting receptors (responsible for our sense of smell and a great part of flavor perception). Of these, more than half have become totally inactive in all humans, a fact that has been known for years. Now a surprising discovery, published in Nature Genetics, shows that at least 50 genes are "optional" they can be active in some individuals and inactive in others. This high level of genetic variation among individuals is most unusual.

A simple calculation, based on the new findings, shows that nearly every human being would display a different pattern of active/inactive receptors an individualized genetic barcode. The uncovered genetic heterogeneity affects the way thousands of aromas and flavors are perceived.

Furthermore, the new research shows that the level of obliteration of olfactory receptors varies among different ethnic groups.

The novel discovery has profound implications for the way the perfume, food and beverage industries handle the discovery of new aroma, flavor and fragrance ingredients. Usually one person, or a small test panel, makes sensory decisions taken to represent billions of customers. But since every nose is different, industry might rethink such issues. The investigators believe that soon a DNA chip could be used to perform olfactory genetics typing of panels and target audiences alike. Thus, cosmetics and foodstuff design would be revolutionized in much the same way that the drug industry now seriously contemplates developing tailor-made medications based on the breakthroughs of pharmacogenetics.